Actuator for a jet pump

Abstract

The invention relates to an actuating unit (10) for a jet pump (100), wherein the actuating unit (10) has a closing element (12) which is configured to close a nozzle (16) of the jet pump (100) so that the nozzle (16) is substantially closed at least temporarily by the closing element (12).

Description

[0001] The invention relates to an actuating unit for a jet pump and a jet pump.

[0002] A variety of jet pumps are known from the prior art. Jet pumps include, in particular, jet pumps and centrifugal pumps. An exemplary jet pump is disclosed in DE 690 23 699 T2. This shows a self-priming centrifugal pump, referred to therein as a jet pump. Starting the pump requires that the inlet opening is completely filled with liquid up to the connection. This also completely fills the injector with the liquid to be pumped. This allows the pumping process of the centrifugal pump to begin.

[0003] A jet pump is particularly characterized by the fact that it has no moving parts. The centrifugal pump is electrically driven and pumps the medium. The jet pump and the centrifugal pump are preferably fluidly connected to one another in the jet pump. Part of the medium that flows through the centrifugal pump is passed through the jet pump so that it can be fed back into the centrifugal pump. By combining the two pumps, the operating range can be expanded compared to a comparable centrifugal pump and, in particular, the achievable discharge pressure can be increased. Furthermore, the jet pump can start up when the inlet line is not yet filled with liquid. A disadvantage of known pumps, however, is that the efficiency of the jet pump can decrease in different operating situations.

[0004] The invention is based on the object of providing an improved jet pump which overcomes the above-mentioned problems.

[0005] This problem is solved by an actuating unit for a jet pump having the features of claim 1. This jet pump has the advantage over known devices in that the actuating unit can close a nozzle or jet pump of a jet pump, allowing switching between different operating modes of the jet pump. For different jet pump tasks, the actuating unit can be used to specifically switch between the operating modes of the jet pump.

[0006] This allows the energy efficiency of the jet pump to be significantly increased and also provides a cost-effective means of achieving optimal pumping results at both high and low differential pressures.

[0007] This is achieved according to the invention in that an actuating unit for a jet pump has a closure element which is designed to substantially close a nozzle of the jet pump at least temporarily.

[0008] In other words, the actuating unit comprises a closure element which is designed to close the jet pump or the nozzle in a force-fitting and / or form-fitting manner, such that the jet pump can be deactivated at least temporarily. The actuating unit can be designed to displace the closure element in such a way that the closure element is at least partially pressed into the nozzle, such that the closure element at least partially seals the nozzle. In this context, “essentially closed” means in particular that a certain residual leakage can remain, wherein the residual leakage can amount to up to 50% of the maximum volume flow through the jet pump. The actuating unit can in particular be arranged near or adjacent to the jet pump, such that the closure element can close off the flow through the jet pump or the nozzle.Furthermore, the actuating unit can be configured to close or block the jet pump in the flow direction as well as against the flow direction of a fluid flowing through the jet pump or nozzle. In this context, "at least temporarily" can mean that the actuating unit is configured to position the closure element for a first period of time such that the nozzle or jet pump is not closed, wherein in a second period of time the actuating unit is configured to close the jet pump or nozzle by means of the closure element. More preferably, in a third period of time the actuating unit can displace or slide the closure element into or out of the nozzle or jet pump so that it is opened or closed again. These sequences can be repeated many times over the service life of a jet pump.Preferably, if the boundary conditions change, the operating mode can be changed multiple times during use of the jet pump. Further preferably, the actuating unit can be configured to position the closure element in any intermediate position between complete closure and complete opening, so that the volume flow through the nozzle or jet pump can be specifically adjusted using the closure element.

[0009] The subclaims show preferred developments of the invention.

[0010] Preferably, the actuating unit is configured to move the closure element into and / or out of the nozzle based on a pressure difference between an inlet side and an outlet side of the jet pump.

[0011] One advantage of this embodiment is that the pressure difference can be used to specifically control when the actuating unit closes the nozzle or the jet pump using the closure element and when not. The closure element can be moved in and out of the nozzle many times over the service life of the jet pump using the actuating unit. In particular, the closing or opening of the nozzle using the closure element can be differentiated between a start-up phase of the jet pump and an operating phase of the jet pump. During the start-up phase of the jet pump, the pressure difference is essentially zero or non-existent. When the jet pump is in operation, the jet pump has already started up, so that a pressure difference can exist between the inlet side and the outlet side. Depending on the pressure difference, the actuating unit can move the closure element into the nozzle or out.from the nozzle in order to close or open the nozzle by means of the closure element. By opening or closing the nozzle by means of the actuating unit, it is possible in particular to change from a first operating characteristic curve, which includes operation of the jet pump and the centrifugal pump, to a second operating characteristic curve, which includes operation of a centrifugal pump alone. Preferably, the nozzle can connect the inlet side to the outlet side in a fluid-conducting manner, so that a corresponding fluid jet can be formed onto the centrifugal pump of the jet pump. In this case, the inlet side can in particular be delimited from the outlet side of the jet pump. The inlet side can be on one side of the jet pump before the fluid has been pumped through the centrifugal pump, and the outlet side can be an area after the fluid has been pumped through the centrifugal pump.The inlet of the nozzle can be directed to the outlet side and the outlet of the nozzle to the inlet side.

[0012] Further preferably, the actuating unit is configured to displace the closure element into the nozzle when a predetermined limit value of the pressure difference is undershot.

[0013] An advantage of this embodiment is that it is possible to switch from a first operating characteristic curve to a second operating characteristic curve of the jet pump if the sole operation of the centrifugal pump leads to a higher degree of efficiency and / or effectiveness than the combination of nozzle or jet pump and centrifugal pump. More preferably, the jet pump can be operated in a normal state in which only the centrifugal pump is active and the jet pump is inactive. If resistances increase in a system supplied by the jet pump, it may be necessary to activate the jet pump in addition to the centrifugal pump in order to ensure the necessary pressure build-up. Furthermore, the nozzle may not be closed by the closure element, but a pressure difference between the inlet side and the outlet side can continuously decrease despite increasing pumping power of the centrifugal pump.As soon as the pressure difference falls below a predetermined limit, the actuating unit closes the nozzle or jet pump using the closure element, so that the centrifugal pump operates alone.

[0014] Preferably, the actuating unit is configured to displace the closure element from the nozzle when the predetermined limit value of the pressure difference is exceeded.

[0015] An advantage of this embodiment can be that, with the aid of a predetermined limit value for the pressure difference, it is possible to switch from sole operation of the centrifugal pump back to simultaneous operation of the centrifugal pump and the jet pump or nozzle. For example, a pressure difference between the inlet side and the outlet side can continuously increase, so that if the predetermined limit value is exceeded, this pressure difference causes the actuating unit to displace the closure element from the nozzle or move the closure element out of the nozzle. Thus, the nozzle or the jet pump can be opened using the actuating unit and the closure element.

[0016] Further preferably, the actuating unit has at least one return element, in particular a spring element, wherein the return element is designed to press the closure element into the nozzle with a predetermined return force.

[0017] An advantage of this embodiment is that the return element is a cost-effective and durable element that can displace the closure element of the actuating unit or the jet pump. Preferably, the spring element can be arranged on an inner side of the jet pump and connected to the closure element. Further preferably, the closure element has a first side facing the outlet side of the jet pump. Preferably, the closure element has a second side facing the inlet side. The return element, in particular the spring element, can be arranged on the second side of the closure element and on an inner side of the jet pump.

[0018] In particular, a higher pressure may prevail on the outlet side than on the inlet side. The higher pressure on the outlet side can act on the first side of the closure element, causing the closure element to be displaced from the nozzle, particularly counter to the restoring force exerted by the restoring element. The restoring force can, in particular, be a spring force of the spring element.

[0019] Preferably, the closure element has a first side which faces the outlet side of the jet pump, wherein the closure element, in particular with the return element, has a second side which faces the inlet side of the jet pump, wherein a return force of the return element is selected such that, when a pressure difference between the outlet side and the inlet side exceeds a predetermined limit value, the closure element is displaced from the nozzle.

[0020] An advantage of this embodiment is that, with the aid of the ratio between the first side and the second side of the closure element in conjunction with the restoring force of the restoring element, it is possible to specifically adjust when the closure element moves out of the nozzle. This can occur in particular when a pressure on the outlet side exceeds a predetermined limit. This can also occur in particular when a pressure difference between the inlet side and the outlet side exceeds the predetermined limit of the pressure difference. In addition, the actuating unit can displace the closure element into the nozzle when the pressure on the outlet side drops and in particular a predetermined limit of the pressure difference between the inlet side and the outlet side is undershot. More preferably, the closure element comprises a third side, which is in particular the tip of the closure element.The third side is a part of the closure element that protrudes into the inlet area when the closure element is in the nozzle, so that the pressure on the inlet side acts on the third side. Furthermore, the pressure on the outlet side can act on the third side if the closure element has been displaced from the nozzle. When the closure element closes the nozzle, the pressure on the outlet side can act on the first side, and the pressure on the inlet side can act on the second and third sides.

[0021] Further preferably, the actuating unit has a starting device with an actuating element and the starting device is designed to overcome the restoring force, in particular by means of the actuating element, and to displace the closure element from the nozzle.

[0022] An advantage of this embodiment is that during the start-up phase of the jet pump, the closure element can be moved out of the nozzle by means of the starting device, thus enabling the centrifugal pump to prime. Thus, the start-up of the jet pump can be made significantly easier with the help of the starting device. For example, the starting device can comprise an actuating element, such as a lever, which is connected to the closure element in a force-conducting manner. The lever can be arranged, for example, on a housing of the jet pump and actuated when the jet pump is started. More preferably, the starting device can comprise an electrical or electromagnetic actuator, which can be activated by the actuating element.

[0023] Preferably, the actuating unit has a pressure channel which connects the inlet side to the outlet side and the closure element is arranged displaceably and / or fluid-tight and at least partially in the pressure channel.

[0024] An advantage of this embodiment is that the pressure channel can be used to ensure that the pressure of the inlet side prevails on the second side of the closure element and the pressure of the outlet side prevails on the first side of the closure element. This makes it possible to create a pressure difference at the closure element between the first side and the second side of the closure element. The closure element can in particular be arranged displaceably and / or in a fluid-tight manner in the pressure channel. For example, the pressure channel has a round cross-section in which a round closure element is arranged. The closure element can in particular be arranged displaceably, in particular displaceable by means of the return element, in the pressure channel.

[0025] Preferably, the closure element has a radial seal to substantially seal the pressure channel.

[0026] An advantage of this embodiment is that the manufacturing costs of the closure element and the pressure channel can be significantly reduced, since any manufacturing inaccuracies can be corrected by the radial seal. For example, the radial seal, in particular, can essentially seal the pressure channel, with "essential" encompassing a deviation of ± 50%. In particular, the radial seal is connected to both the closure element and the pressure channel.

[0027] Further preferably, the actuating unit comprises an actuator which is configured to move the closure element into the nozzle and / or out of the nozzle.

[0028] An advantage of this embodiment is that, with the aid of an actuator, it is possible to specifically adjust when the closure element is moved out of or into the nozzle. Furthermore, any further position between a complete opening and a complete closing of the closure element can be specifically controlled with the aid of the actuator. For example, the actuator can be any type of unit that generates a movement from an electrical signal current. In particular, the actuator can be designed such that it changes the position of the closure element, particularly along an axis.

[0029] Further preferably, the actuating unit comprises a control unit which can be connected to at least one first sensor element, wherein the control unit is configured to displace the closure element out of the nozzle and / or into the nozzle by means of the first sensor element when a predetermined reference is exceeded or undershot at the first sensor element.

[0030] An advantage of this embodiment is that, with the aid of a single sensor element and the predetermined reference, it is possible to decide when the nozzle is to be opened or closed by the closure element. This allows, in particular, the total number of components in the jet pump or the actuating unit to be reduced, thus saving costs. Preferably, the first sensor element is arranged on the outlet side of the jet pump. The first sensor element can, in particular, be a pressure sensor, flow sensor, or any type of sensor configured to detect a point at which the nozzle is to be closed or opened.

[0031] Further preferably, the control unit is connectable to a second sensor element, wherein the control unit is configured to determine a difference value between the first sensor element and the second sensor element, wherein the control unit is configured to displace the closure element out of the nozzle when a difference value exceeds a difference limit value and / or to displace the closure element into the nozzle when the difference value falls below the limit value.

[0032] An advantage of this embodiment is that, with the aid of the first sensor element and the second sensor element, the differential value or the pressure difference between the inlet side and the outlet side can be precisely determined. Depending on the differential value, a decision can be made as to whether the actuating unit blocks and / or opens the nozzle using the closure element. The actuating unit can displace or move the closure element out of the nozzle if the current differential value exceeds and / or exceeds a differential limit. More preferably, the actuating unit can displace or move the closure element into the nozzle if the differential value falls below or is smaller than the differential limit.

[0033] Further preferably, the control unit is configured to receive a start signal, wherein the control unit is configured to substantially open the nozzle by means of a closure element upon receipt of the start signal.

[0034] An advantage of this design is that at the start or during the start-up phase of the jet pump, the control unit with the actuator can move the closure element out of the nozzle or jet pump based on the start signal, so that the jet pump is self-priming during the start-up phase or the beginning of operation. Once the start-up phase of the jet pump is complete, the jet pump control system can return to normal operation.

[0035] Preferably, a pressure applied to the closure element, in particular with actuator, is substantially constant and in particular this substantially corresponds to a pressure on the outlet side.

[0036] An advantage of this design is that when there is no pressure difference across the closure element, significantly less force is required by the actuator to move the closure element into or out of the nozzle. Essentially, in this context, this means a deviation of ± 50%.

[0037] Preferably, the actuator has at least one permanent magnet.

[0038] One advantage of this embodiment is that by means of the actuator, which is preferably arranged inside the jet pump, an outer wall does not have to be perforated, since all elements for closing the nozzle are located inside the housing. This means that the number of sealing points can be reduced. A further advantage is that with the help of the permanent magnet, a magnetic drive can be designed which is particularly low-wear, so that the operating time of the actuating unit can be significantly increased. For example, a first permanent magnet can be arranged on the closing element and a second permanent magnet on an inner side of the jet pump. By changing the polarity between the permanent magnets, it can be adjusted whether the closing element closes the nozzle or the closing element is spaced from the nozzle.

[0039] Preferably, the control unit is configured to adapt the predetermined reference based on the reset element.

[0040] An advantage of this embodiment is that when the actuator is extended by the return element, the reference for opening or closing the nozzle can be adapted to the return element by means of the closure element.

[0041] Further preferably, the force for displacing the closure element from the nozzle by means of the actuator when the closure element is in contact with the nozzle can be calculated. In this case, pressures can be applied to the closure element that are attributable to the outlet side when the closure element has been displaced from the nozzle. The force can be calculated using the following formula: Fp,Zu=π4D12(pH−pN)

[0042] Further preferably, the actuator can control the force F p,Zuwhich is needed to move the closure element out of the nozzle and thus open the nozzle. Furthermore, p H a pressure in the outlet side of the jet pump. Furthermore, p N the pressure on the inlet side of the jet pump. For example, the maximum discharge pressure of the nozzle or jet pump can be between 4 bar and 6 bar. The maximum discharge pressure of the centrifugal pump can be approximately between 2 bar and 3 bar. Furthermore, the maximum volume flow of the jet pump can be between 3000 and 5000 l / h. D1 can preferably be the diameter of the closure element on the first side, in particular a diameter that essentially closes the nozzle. This diameter can be, for example, between 5 and 15 mm.

[0043] Preferably, the actuating unit, with both a return element and an actuator, can open the nozzle at a predetermined criterion, such as Δp > Δp Entsperrung. Δp Entsperrung be chosen so that it is just below the maximum discharge pressure of the centrifugal pump. For example, Δp Entsperrung in a range between 1.5 bar and 2.5 bar. Furthermore, the differential pressure may drop during further operation, so that the actuator should close the nozzle, for example, at Δp Sperrung . In particular, Δp < Δp Sperrung apply.

[0044] Further preferably, the return element or the spring element, in particular for Δp Entsperrung , can be dimensioned using the following formula: −π4(D22−D12)ΔpUnlock−K(LZu−L0)+Fμ=0

[0045] Here, D2 is the second diameter of the closure element, and D1 is the first diameter of the closure element. When the closure element is connected to the spring element, D2 can always be larger than D1. For example, D2 can be in a range from 10 mm to 30 mm. D1 can also be in a range from 5 mm to 25 mm. K can be the spring constant of the spring element and can be in a range from 1 N / mm to 1.5 N / mm. zu can also be the length of the spring when the nozzle is closed by the closure element and can range, for example, from 30 mm to 50 mm. L0 can also be the length of the spring at rest and can range, for example, from 40 mm to 60 mm. The resulting restoring force or spring force of the spring element could be in a range between 20 and 30 N. F µ This can be the frictional force that can arise from the displacement of the locking element.

[0046] More preferably, a cross-section of the closure element on the second side can be determined using the following formula: π4D22(ΔpUnlock−ΔpLock)=2|Fμ|+π4D12ΔpLock

[0047] Furthermore, the spring constant of the return element and the preload can be determined using the following formula: −π4(D22−D12)ΔpBlock−K(LZu−L0)+Fμ=0

[0048] A further aspect relates to a jet pump having an inlet side and an outlet side, wherein a centrifugal pump is arranged between the inlet side and the outlet side, wherein the jet pump has a nozzle connecting the inlet side to the outlet side, wherein the actuating unit, as described above and below, is configured to temporarily substantially close the nozzle.

[0049] The actuating unit can be arranged, in particular, between the inlet and outlet sides. Further preferably, a fluid to be transported or compressed is sucked in on the inlet side of the jet pump and discharged at increased pressure on the outlet side.

[0050] In addition to the above written description of the invention, reference is hereby explicitly made to the drawings depicting the invention in the figures for the purpose of supplementing its disclosure. In the drawing: Fig. 1 to 4 an actuating unit according to a first embodiment, Fig. 5 and Fig. 6 an actuating unit according to a second embodiment, Fig. 7a and Fig. 7b a closure element according to a third embodiment, Fig. 8 a closure element according to a fourth embodiment, Fig. 9 and Fig. 10 diagrams illustrating the operation of the actuator according to a fifth embodiment, Fig. 11 an actuating unit according to a sixth embodiment, and Fig. 12 a jet pump according to a seventh embodiment. Embodiments of the invention

[0051] Preferably, all identical components, units and / or elements in all figures are provided with the same reference numerals.

[0052] Fig. Figure 1 shows an actuating unit 10 for a jet pump 100 according to a first embodiment. The actuating unit 10 comprises a closure element 12. The closure element 12 is configured to substantially close the nozzle 16 of the jet pump 100, at least temporarily.

[0053] Furthermore, Fig. 1 shows the actuating unit 10 with the closure element 12, wherein the closure element 12 is displaced into the nozzle 16 or displaced out of the nozzle 16 when a pressure difference between an inlet side 102 of the jet pump 100 and an outlet side 104 of the jet pump 100 exceeds or falls below a predetermined limit value. In this case, the actuating unit 10 has, in particular, a restoring element or spring element 18. The spring element 18 is designed to press the closure element 12 into the nozzle 16. The predetermined restoring force of the spring element 18 can be adapted to a type or type of actuating unit 10 and / or the jet pump 100. In addition, the closure element 12 comprises a first side 20, which faces the outlet side 104 of the jet pump 100. Furthermore, the closure element 12 comprises a second side 22 which faces the inlet side 102 of the jet pump 100.The second side 22 and the first side 20 are particularly designed such that a prevailing pressure in the inlet side 102 and / or the outlet side 104 can act on the corresponding sides. The restoring force of the spring element 18 is selected such that, if a pressure difference between the outlet side 104 and the inlet side 102 exceeds a predetermined limit value, the closure element 12 is displaced from the nozzle 16. The closure element 12 also has a sealing side 14 or third side, which is designed to form a positive and / or non-positive connection with the nozzle 16. Furthermore, the closure element 12 has a first diameter 46 on the first side 20 and a second diameter 50 on the second side 22.Depending on the ratio between the first diameter 46 and the second diameter 50 and the dimensioning of the spring element 18, the predetermined limit value at which the closure element 12 is displaced from the nozzle 16 can be defined. As shown in . Fig. 1, the jet pump 100 is in a non-operational state. In order to start operation of the jet pump 100, the actuating unit 10 can have a starting device 24 with an actuating element 26. By moving the actuating element 26, the restoring force of the spring element 18 can be overcome and the closure element 12 can be displaced from the nozzle 16. More preferably, the closure element 12 can be arranged on the side of the nozzle 16 that faces the centrifugal pump 112 and / or as shown in the Fig. 1 shown on the side of the nozzle 16 which is facing away from the centrifugal pump 112.

[0054] Fig. 2 shows an actuating unit 10 in a start-up phase of the jet pump 100. During the start-up phase, the actuating element 26 of the starting device 24 is moved into a second position, in which the starting device 24 overcomes the restoring force of the spring element 18 and moves the closure element 12 out of the nozzle 16. In this state, the operation of the jet pump 100, in particular the centrifugal pump 112, can begin. As shown in the Fig. 2, a radial seal 30 is arranged on the closure element 12. The radial seal 30 essentially seals a gap between the closure element 12 and the pressure channel 28. The pressure channel 28 can in particular be designed to fluidically connect the inlet side 102 to the second side 22 of the closure element 12. More preferably, the closure element 12 is displaceably arranged in the pressure channel 28. The pressure of the outlet region 104 can in particular be applied to the first side 20 of the closure element 12. Furthermore, the prevailing pressure in the inlet region 102 can be applied to the second side 22 of the closure element 12.

[0055] Fig. Figure 3 shows the actuator unit 10 during operation. The increased pressure in the outlet area 104 of the jet pump 100 pushes the closure element 12 of the actuator unit 10 out of the nozzle 16, since the pressure on the inlet side 102 is lower than on the outlet side 104. The starting device with the actuating element 26 is in the first position, so to speak, deactivated.

[0056] Fig. 4 shows the actuating unit 10 according to the first embodiment during operation of the jet pump 100. During operation of the jet pump 100, situations may arise in which the prevailing pressure in the outlet region 104 of the jet pump 100 is no longer sufficient to displace the closure element 12 from the nozzle 16. Thus, the restoring force of the spring element 18 is preferably greater than the force generated on the closure element 12 by the pressure difference between the inlet side 102 and the outlet side 104 of the jet pump 100. Thus, the closure element 12 is displaced into the nozzle 16, so that only the pumping power of the centrifugal pump 112 is present on the outlet side 104.

[0057] Fig. 5 shows an actuating unit 10 according to a second embodiment. The actuating unit 10 comprises a closure element 12, which can be moved into the nozzle 16 by means of an actuator 32, as well as out of the nozzle 16. In this embodiment, the closure element 12 is preferably arranged entirely in the outlet side 104, so that the pressure prevailing in the outlet side 104 acts on the closure element 12, in particular from all sides. The actuating unit 10 preferably comprises a control unit 34, which is configured to control the movement of the closure element 12 using a first sensor element 36. The first sensor element 36 can be arranged, in particular, in an outlet side 104 of the jet pump 100.Depending on the direction in which the prevailing pressure in the outlet side 104 changes, the control unit 34 and the first sensor element 36 can determine when the actuator 32 will move the closure element 12 out of the nozzle 16 and / or into the nozzle 16. For example, the closure element 12 can be moved into the nozzle 16 when the prevailing pressure in the outlet side 104 falls below a predetermined reference. Furthermore, the closure element 12 can be moved out of the nozzle 16 when the pressure in the outlet side 104 exceeds the predetermined reference. During a start-up phase of the jet pump 100, the actuator 32 can move the closure element 12 out of the nozzle 16 based on the start signal.

[0058] Further preferably, a pressure difference between the outlet side 104 and the inlet side 102 can be determined by means of a second sensor element 38, which is preferably arranged in the inlet side 102 of the jet pump 100, and the first sensor element 36, which is arranged in particular on the outlet side 104 of the jet pump 100. Depending on the pressure difference, the closure element 12 can be displaced from the nozzle 16 or displaced into the nozzle 16.

[0059] Furthermore, the closure element 12, which can be connected to the return element and / or the actuator, comprises a sealing side 14, which can in particular form a force-locking and / or positive connection with the nozzle 16. When the closure element 12 is in the nozzle 16, a negative pressure can develop at a tip 40 of the closure element 12, since the pressure on the inlet side 102 is preferably lower than the pressure on the outlet side 104 of the jet pump 100. Thus, the actuator 32 should be able to develop sufficient force to overcome the negative pressure at the tip 40 in order to displace the closure element 12 from the nozzle 16.

[0060] Fig. 6 shows the jet pump 100 as it has already been designed with regard to Fig. 5 was explained. In the Fig. 6, the actuator 32 has displaced the closure element 12 into the nozzle 16, so that the closure element 12 closes the nozzle 16. This can occur if a difference value between the first sensor element 36 and the second sensor element 38 falls below a difference limit.

[0061] Fig. 7a and Fig. 7b show an embodiment of the closure element 12, which can be operated in particular in cooperation with the actuator 32. The closure element 12 has a permanent magnet 42. Furthermore, in the Fig. 7a shows a portion of the actuator 32. By rotating the portion of the actuator 32, the polarization of the disk 33 can be changed, so that the closure element 12 is either pushed into the nozzle 16 or pulled out of it by the magnetic and / or electromagnetic force. Further preferably, the closure element 12 can have a sealing seat 44, such as an O-ring seal, to improve the seal between the closure element 12 and the nozzle 16.

[0062] Fig. 8 shows a closure element 12 on which a return element or spring element 18 is arranged. In particular, the closure element 12 can have a closure surface 14, which is designed to close the nozzle 16 or the jet pump of the jet pump 100. More preferably, the closure element 12 can have a sealing seat 44, such as an O-ring seal, to improve the seal between the closure element 12 and the nozzle 16. Furthermore, the closure element 12 can have a radial seal 30, which in particular separates the inlet side 102 from the outlet side 104.

[0063] Fig. 9 shows a diagram to illustrate the functioning of the actuating unit 10 according to one embodiment. In the diagram 120, a first axis 122 is shown, on which a pressure difference between the inlet side 102 and the outlet side 104 is shown, as well as a second axis 124, on which the volume flow is shown. In the diagram 120, a first curve 126 is shown, which represents a characteristic curve of the jet pump 100 with a permanently open nozzle 16. Furthermore, a second curve 128 shows a characteristic curve of the jet pump 100 with a permanently closed nozzle 16. Furthermore, the diagram 120 shows a third characteristic curve 130, which represents the operation of the jet pump 100 with the actuating unit 10, wherein at a predetermined pressure difference, the closure element 12 closes or opens the nozzle 16. As in the Fig. As can be seen from Figure 9, the actuating unit 10 and the closing or opening of the nozzle 16 enable the actuating unit 10 to switch to different operating characteristics, thus enabling optimized operation of the jet pump 100 to be achieved.

[0064] Fig. 10 shows a second diagram 132. The second diagram 132 includes a first axis 134 on which the efficiency is plotted. The second diagram 132 also includes a second axis 136 on which the volume flow is shown. The second diagram 132 also shows a first characteristic curve 138. The first characteristic curve 138 shows the efficiency of the jet pump 100 with a permanently open nozzle 16. The second diagram 132 also shows a second characteristic curve 140, which represents the operation of the jet pump 100 with a controlled opening and closing of the nozzle 16 by means of the actuating unit 10. The second diagram 132 also shows a third characteristic curve 142, which represents the efficiency with a permanently closed nozzle 16.

[0065] Fig. 11 shows an actuating unit 10 which comprises a closure element 12 which is designed to at least temporarily close a nozzle 16 of a jet pump 100.

[0066] Fig.12 shows a jet pump 100 having a centrifugal pump 112. Furthermore, the jet pump 100 includes an actuator 10, as described above and below. Furthermore, the jet pump 100 includes a nozzle 16, which connects, in particular, an inlet side 102 to an outlet side 104. List of reference symbols 10 Actuator 12 locking element 14 Sealing side 16 nozzle 18 Reset element 20 first page 22 second page 24 Starting device 26 Actuating element 28 pressure channel 30 radial seal 32 Actuator 34 Control unit 36 first sensor element 38 second sensor element 40 lace 42 permanent magnet 44 Sealing seat 46 first diameter 50 second diameter 100 jet pump 102 Inlet side 104 Outlet page 112 Centrifugal pump 120 Diagram 122 first axle 124 second axle 126 first curve 128 second curve 130 third characteristic curve 132 second diagram 134 first axle 136 second axle 138 first characteristic curve 140 second characteristic curve 142 third characteristic curve QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 690 23 699 T2

[0002]

Claims

[1] Actuating unit (10) for a jet pump (100), wherein the actuating unit (10) has a closure element (12) which is designed to substantially close a nozzle (16) of the jet pump (100) at least temporarily. [2] Actuating unit (10) according to claim 1, wherein the actuating unit (10) is configured to displace the closure element (12) into and / or out of the nozzle (16) based on a pressure difference between an inlet side (102) and an outlet side (104) of the jet pump (100). [3] Actuating unit (10) according to claim 2, wherein the actuating unit (10) is configured to displace the closure element (12) into the nozzle (16) when a predetermined limit value of the pressure difference is undershot. [4] Actuating unit (10) according to claim 3, wherein the actuating unit (10) is configured to displace the closure element (12) from the nozzle (16) when the predetermined limit value of the pressure difference is exceeded. [5] Actuating unit (10) according to one of the preceding claims, wherein the actuating unit (10) has at least one restoring element (18), in particular a spring element, which is designed to press the closure element (12) into the nozzle (16) with a predetermined restoring force. [6] Actuating unit (10) according to claim 5, wherein the closure element (12) has a first side (20) which faces the inlet side (102) of the jet pump (100), wherein the closure element (12) has a second side (22) which faces the outlet side (104) of the jet pump (100), wherein a restoring force of the restoring element (18) is selected such that, when a pressure difference between the outlet side (104) and the inlet side (102) exceeds a predetermined limit value, the closure element (12) is displaced from the nozzle (16). [7] Actuating unit (10) according to claim 6, wherein the actuating unit (10) has a starting device (24) with an actuating element (26) and the starting device (24) is designed, in particular by means of the actuating element (26), to overcome the restoring force and to displace the closure element (12) from the nozzle (16). [8] Actuating unit (10) according to one of claims 5 to 7, wherein the actuating unit (10) has a pressure channel (28) which connects the inlet side (102) to the outlet side (104) and the closure element (12) is arranged displaceably and / or fluid-tight and at least partially in the pressure channel (28). [9] Actuating unit (10) according to claim 8, wherein the closure element (12) has a radial seal (30) to substantially seal the pressure channel (28). [10] Actuating unit (10) according to one of the preceding claims, wherein the actuating unit (10) comprises an actuator (32) which is designed to displace the closure element (12) into and / or out of the nozzle (16). [11] Actuating unit (10) according to claim 10, wherein the actuating unit (10) has a control unit (34) which can be connected to at least one first sensor element (36), wherein the control unit (34) is designed to displace the closure element (12) out of the nozzle (16) and / or into the nozzle (16) by means of the first sensor element (36) when a predetermined reference is exceeded or undershot at the first sensor element (36). [12] Actuating unit (10) according to one of claims 10 to 11, wherein the control unit (34) is connectable to a second sensor element (38) and is configured to determine a difference value between the first sensor element (36) and the second sensor element (38), wherein the control unit (34) is configured to displace the closure element (12) from the nozzle (16) when the difference value exceeds a difference limit value and / or to displace the closure element (12) into the nozzle (16) when the difference value falls below the difference limit value. [13] Actuating unit (10) according to one of claims 10 to 12, wherein a pressure applied to the closure element (12) is substantially constant and in particular substantially corresponds to a pressure in the outlet region (104). [14] Actuating unit (10) according to claims 5 and 11, wherein the control unit (34) is configured to adapt the predetermined reference based on the reset element (18). [15] Jet pump (100) comprising an inlet side (102) and an outlet side (104), wherein a centrifugal pump (112) is arranged between the inlet side (102) and the outlet side (104), wherein the jet pump (100) has a nozzle (16) which connects the inlet side (102) to the outlet side (104), wherein the actuating unit (10) according to one of the preceding claims is designed to temporarily substantially close the nozzle (16).

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